ServerSocket.accept() doesn't works in second time

Question

I'm beginer in android and i'm trying develop a connection TCP server.

I have this class:

public class JavaTCPServer {


public static void send(String aMessage) {

    final String msg = aMessage;

    Thread thread = new Thread(new Runnable() {

        @Override
        public void run() {
            Socket socket = null;
            try {

                ServerSocket serverSocket = GlobalSingleton.getInstance().getServerSocket();

                socket = serverSocket.accept();

                PrintWriter printWriter = new PrintWriter(socket.getOutputStream(), true);

                printWriter.println(msg);

                printWriter.flush();
                printWriter.close();

            } catch (IOException ex) {
                ex.printStackTrace();
            } finally {

                if (socket != null) {
                    try {

                        socket.close();
                        socket = null;
                    } catch (IOException ex) {
                        ex.printStackTrace();
                    }
                }

            }
        }
    });

    thread.start();

}


}


private ServerSocket serverSocket; //Created in GlobalSingleton Class...


try {
            serverSocket = new ServerSocket(Constantes.TCP_PORT);
        } catch (IOException e) {
            e.printStackTrace();
        }

I can send message normally in the first time, but when i try to send message the second time the software remains in line: socket = serverSocket.accept(); and the message in printWriter.println(msg) is not sent.

Additional Information

When i kill the app in settings and open i can send once.

Any questions don't hesitate ask me.

Thanks for all!

Answer 1

I solved my own problem.

I wrote my class as the follow bellow code:

public class JavaTCPServer {

    private ServerSocket serverSocket;
    private String message;
    private Handler updateConversationHandler;
    private Thread serverThread = null;

    public String getMessage() {
        return message;
    }

    public void setMessage(String message) {
        this.message = message;
    }

    public ServerSocket getServerSocket() {
        return serverSocket;
    }

    public void setServerSocket(ServerSocket serverSocket) {
        this.serverSocket = serverSocket;
    }

    public JavaTCPServer() {

        setUpdateConversationHandler(new Handler());
        this.serverThread = new Thread(new ServerThread());
        this.serverThread.start();

    }

    public Handler getUpdateConversationHandler() {
        return updateConversationHandler;
    }

    public void setUpdateConversationHandler(Handler updateConversationHandler) {
        this.updateConversationHandler = updateConversationHandler;
    }

    class ServerThread implements Runnable {

        public void run() {
            Socket socket = null;
            try {
                serverSocket = new ServerSocket(Constantes.TCP_PORT);
            } catch (IOException e) {
                e.printStackTrace();
            }
            while (!Thread.currentThread().isInterrupted()) {
                try {
                    socket = serverSocket.accept();
                    CommunicationThread commThread = new CommunicationThread(
                            socket);
                    new Thread(commThread).start();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

    class CommunicationThread implements Runnable {

        private Socket clientSocket;
        private BufferedReader input;
        private String messageSend;

        public CommunicationThread(Socket clientSocket) {
            this.clientSocket = clientSocket;

            try {
                this.setInput(new BufferedReader(new InputStreamReader(
                        this.clientSocket.getInputStream())));
            } catch (IOException e) {
                e.printStackTrace();
            }
        }

        public void run() {
            while (!Thread.currentThread().isInterrupted()) {

                Central central = GlobalSingleton.getInstance()
                        .get_current_central();

                if (central != null) {

                    if ((central.getStep() <= central.getObjetivo()) &&
                       (central.getStep() == 99)){

                        try {

                            messageSend = getMessage();

                            PrintWriter printWriter = new PrintWriter(
                                    clientSocket.getOutputStream(), true);

                            printWriter.println(messageSend);
                            printWriter.flush();
                            try {
                                Thread.sleep(1500);
                            } catch (InterruptedException e) {
                                e.printStackTrace();
                            }
                            printWriter.println(Constantes.EXIT_CONFIG);
                            printWriter.flush();
                            try {
                                Thread.sleep(500);
                            } catch (InterruptedException e) {
                                e.printStackTrace();
                            }

                        } catch (IOException e) {
                            e.printStackTrace();
                        }

                        central.setStep(central.getStep() + 1);
                    }
                }

                /*
                 * try { String read = input.readLine();
                 * updateConversationHandler.post(new updateUIThread(read)); }
                 * catch (IOException e) { e.printStackTrace(); }
                 */
            }
        }

        public BufferedReader getInput() {
            return input;
        }

        public void setInput(BufferedReader input) {
            this.input = input;
        }
    }

}

With this class you can send and receive tcp messages all the time.

Thanks for all help!